Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 72
Original Shlokaमेरुमन्दरसङ्काशानुद्धतान् स महार्णवे। अत्यक्रामन्महावेगस्तरङ्गान् गणयन्निव।।5.1.72।।
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महावेगः one who is of high speed, महार्णवे in the ocean, उद्धतान् risen, मेरुमन्दरसङ्काशान् resembling mountain Meru and Mandara, तरङ्गान् waves, गणयन्निव as if counting, सः that, अत्यक्रामत् crossed.
Hanuman moving along in high speed looked as if he was counting the mighty waves risen ike Meru and Mandara mountains.